A new paper published in the journal Animal Behavior tackles the origin of the female orgasm—does it have gender-specific advantages, or is it merely a byproduct of male adaptations? Having polled 10,000 twins about their orgasmic tendencies, researchers found “no significant correlation between opposite-sex twins and siblings” and therefore concluded that “selection pressures on male orgasmic function do not act substantively on female orgasmic function.” PZ Myers writes “the logic of this experiment falls apart at every level.” He points to the inevitable biases that affect self-reporting, and the fact that researchers asked male and female twins qualitatively different questions. PZ concludes, “I’d consider it extremely unlikely that female orgasm doesn’t use exactly the same genetic apparatus as male orgasm.” Greg Laden criticizes the research as well, writing “the reason that the Zietsch and Stanttila paper is wrong, in my view, is because it asks the wrong question in the wrong way with an incorrect understanding of what they are studying and why.” Greg says most researchers are (figuratively) blinded by the ejaculation of seminal fluid by males. And he offers some very interesting insights into the development of erogeneity in primates, and its refinement in the human species.